Then in the second round, in which competitors had only 20 minutes to prepare an "instant dance" – a jive – Martinez and Smirnoff repeated the perfect feat with another 30 points, and another standing ovation.

"Now you've got the X-factor and the feel-good factor mixed together, and you come out here with the most fantastic jive," said Len Goodman.

Behind them were Ricki Lake and Derek Hough, who scored 28 points with their first-round waltz that Carrie Ann Inaba called "exquisite." But their 24-point second-round instant jive brought them down a notch.

They were tied for the night with Hope Solo and Maksim Chmerkovskiy who also collected 27 points for a first-round quickstep that Tonioli found "light, breezy." Their instant jive boosted them by another 25 points.

Rob Kardashian and Cheryl Burke got 27 points for their quickstep that started out badly but picked up. Their instant dance garnered another 24 points.

But Nancy Grace was on the brink of leaving the ballroom. Her tango with Tristan McManus got encouraging comments from the judges – "You are the friskiest girl I've ever met," said Inaba – but a score of only 24.

Not even a performance-ending cartwheel could save Grace's instant jive, which got just 20 points.